<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title>提示圆点</title>
	</head>
	<style>
		.parent{
			position: relative;
			width: 100px;
			height: 100px;
			background-color: aqua;
		}
		
		.child{
			position: absolute;
			top: -10px;
			right: -10px;
			background-color: #b92b27;
			height: 20px;
			width: 20px;
			border-radius:100%;
			border: 2px solid #fff;
		}
		.child a{
			display: block;
			height: 20px;
			line-height: 20px;
			width: 20px;
			text-align: center;
			color: #fff;
		}
	</style>
	<body>
	
		
		<div class="parent">
			<div class="child">
				<a>1</a>
			</div>
		</div>
	</body>
</html>